Sunlight‐Responsive Photothermochromic Fabric with Reversible Color Changing Based on Photothermal Conversion

Abstract

Intelligent color‐changing textiles have attracted increasing attention due to their potential application in healthcare monitoring and artificial intelligence. To realize the active modulation of color via sunlight, the photothermochromic fabric that adjusts its color based on the photothermal conversion performance of the sunlight‐responsive heating layer under irradiation of solar is fabricated by double‐side coating. Depending on the light absorption at 350–2500 nm, the sunlight‐responsive photothermochromic fabric (SPTCF) exposed under the irradiation power density of 500 W m−2 for 4 min displays efficient photothermal conversion, resulting in the increase in temperature from room temperature (23.0 °C) to above 47.0 °C. Simultaneously, the color of SPTCF changes from blue to white and returns to blue once the light is turned off for 3 min, indicating the sensitive and reversible photothermochromic property of the SPTCF. Compared with the contrast layer, the sunlight‐responsive heating layer exhibits a rapid photothermal conversion speed and high optical contrast under the same irradiation condition. The heating/cooling curves show steady signals after mechanical deformations and 150 cycles, revealing the favorable durability of the SPTCF under the solar irradiation. The sensitive photothermochromic properties promote the application of the SPTCF in smart wearable fields.

Storing energy with molecular photoisomers

“…The transparency may be useful in applications, such as energy efficient windows, 101 and the structural flexibility may be useful in functional fabrics with thermal control and energy transfer functions. 147 The opportunity to store energy in a compact, local way and to release it on demand as heat may also lead to new hybrid systems for power production without the need for traditional batteries. Although up to 1.1% solar energy conversion efficiency has been demonstrated for MOST system in its current state, 124 it is still far from the performance of more traditional energy storage systems.…”

SMART Wearable Fabric using Electronic Textiles – A Review

“…Its fabric provides a pleasant handfeel and is washing-resistant. [12,17,18] temperature control fabric water-proof &breathable fabric…”

Three‐Output Naked‐Eye High Temperature Organic Film Threshold Thermometers Based on Non‐Invasive Chemical Reaction

“…[ 13,20,30,31 ] Moreover, these thermochromic fluorophores may further explore their applications in fields such as energy saving, anticounterfeiting, bioimaging, optical modulation, storage devices, and wearable electronics. [ 32–35 ]…”

“…Luminescent temperature sensors [1][2][3][4][5][6][7][8][9][10] and threshold thermosensors, [11][12][13][14] which exhibit thermal changes in fluorescence intensity, ratiometric fluorescence or fluorescence lifetime, have attracted considerable attention due to their ability bioimaging, optical modulation, storage devices, and wearable electronics. [32][33][34][35] As for luminescent threshold thermometers, the design principles are mainly based on two kinds of temperature-dependent luminescent signals, that is, the monochromic and ratiometric emission intensities. In monochromic systems, the boosting of fluorescence intensity is usually triggered by thermally driven disaggregation or phase transition.…”